The Kantorei St. Jacobi (= KSJ; Choir of St. Jacobi Cathedral Hamburg) at the Hauptkirche (main church) St. Jacobi in Hamburg exists since 1958. It was created by the Kantor and organist of the church at that time, the renowned organ virtuoso Heinz Wunderlich, as big oratorio choir and already from the year of the foundation consists constantly between 80 and 100 singers. Since 1982 Rudolf Kelber leads the tapered KSJ.
During the years of its existence the KSJ has performed almost completely the Baroque and Romantic oratorio repertoire, beginning with Schütz over numerous works George Frideric Handel's (partially in scene performances), Haydns oratorios, Mozart's Masses and Requiem, Beethoven's Missa Solemnis, up to Felix Mendelssohn, Johannes Brahms, Dvorak and Verdi. In the center of their musical interest, as well as also that of the public always confessed the works J.S. Bach. Markus-Passion (BWV 247) (in the reconstruction of Rudolf Kelber) is present in a CD recording.
Apart from the music of the post-Reformation early Baroque (Michael Praetorius, Johann Eccard, Matthias Weckmann, Johann Hermann Schein, etc.) a special attention is given of the interpretation of Romantic a-capella music (J. Brahms, Bruckner, Max Reger, Josef Rheinberger) and modern sacred music (works of von Maurice Duruflé, Zoltán Kodály, Igor Stravinsky, Francis Poulenc, Martin, Messiaen, Penderecki, Benjamin Britten and v. Kameke).
Two instrumental ensembles accompany since 1983 and/or 1986 the oratorio and cantata performances of the KSJ: the St. Jacobi-Orchester, recently renamed Concertone Hamburg, which is to be heard also in performance of big symphonic works, and the Cythara Ensemble for the delicate tasks with historical instruments.
In the course of its existence the KSJ has undertaken numerous tours abroad, including Switzerland (1960, 1976 and 1984), Sweden (1966), France (1968 and 1986), UK (1970, 1972 and 1975), the USA (1978), Finland (1983), Italy (1984) and together with the St. Jacobi-Orchester to Brussels and Paris (1986). A tour to Israel took place in 1988 on invitation of the Israeli Chamber Orchestra. Tours to Riga, Talinn and St. Petersburg (1992), Dresden, Prague, Budapest and Vienna (1996), Arnstadt, Bayreuth and Salzburg (2000), as well as Bautzen, Kreisau, Breslau and Krakau (2002) are the provisional high points of these activities.